1. Field of the Invention
The invention relates to a portable electronic device having a touch-sensitive screen, and more particularly, to a method of modifying the size of soft buttons displayed on a touch-sensitive screen of an electronic device for improving the accuracy of selecting a soft button.
2. Description of the Prior Art
Touch-sensitive screens are becoming a popular way to enter text and commands into a portable electronic device. However, as the size of portable electronic devices shrinks, so does the size of the touch-sensitive screens. Therefore, it becomes harder to accurately select a soft button displayed on the touch-sensitive screen without accidentally selecting a different soft button that neighbors the soft button that was intended to be selected.
When an incorrect soft button is selected by a user, the user has to go back and correct the incorrect entry, causing the user to spend a greater deal of time entering text and leading to increased frustration.
Attempts have been made in the prior art to help solve this problem. FIG. 6 shows a prior art phone 200 having a soft button that is magnified in response to receiving touch input on a touch-sensitive screen 206. This phone 200 has been marketed as an iPhone® sold by Apple, Inc. When the touch-sensitive screen 206 is pressed, a soft button 204 corresponding to the touch position is magnified, while the size of all other soft buttons 202 remains unchanged. In the example shown in FIG. 6, the soft button 204 is located under the user's finger, and displays the letter “U”. Thus, the prior art provides a way for showing the user's selection and allowing the user to correct. The prior art does not magnify the other nearby soft buttons 202 for assisting in the user's next selection.
FIG. 7 shows a prior art task bar 250 illustrating another example of magnification in a user interface. This task bar 250 is known as the Dock in Mac OS®, which is an operating system made by Apple, Inc. In order to select an item in the task bar 250, the user points the mouse at an icon and clicks on the icon. In order to assist the user with selecting an icon, icons magnify as the user moves the mouse cursor over them. In other words, the mouse acts as a magnifying class as it passes over the icons of the task bar 250. In FIG. 7, when the mouse is over icon 258, icon 258 is magnified the greatest amount of all the icons. Icons 256 and 260 are adjacent to icon 258, and are magnified slightly less than icon 258. Icons 254 and 262 are each two icons away from icon 258, and are magnified slightly less than icons 256 and 260. All other icons 252 are unmagnified and are shown in their normal size. One point worth noting is the task bar 250 is not used in conjunction with a touch-sensitive screen, and is not used to select soft buttons of a keyboard. The icon magnification is also regarded as a special graphical effect, and is not intended for assisting in accuracy of the user's selection.